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new transformer - performance
HI all,
Some weeks ago, I had the opportunity to exchange my 13.8Kv / 5kva pole
pig for a 33kv / 15 kva pole pig at no charge. It arrived about 2 days ago
and I reset my coil up with the new pig and sat down to enjoy the show.
Now I had expected that with the higher voltage the gap would begin to
fire at a lower current setting so I adjusted everything and powered up -
nothing!, I slowly increased the current setting with the voltage set at
about 20kv, finally the gap began to fire at 60 AMPS!! I almost got a nose
bleed when I saw the meters move.
I've tried all sorts of settings right up to 270V input from the voltage
variac, (35640V out) and different current settings on the current control
variac and no difference - no gap activity until at least 50 amps is on
it's way into the pig.
Coil specs -
0.09uF MMC, (33 caps in series, 9 strings)
200BPS sync rotary 4 stationary electrodes
all tank cables are 0 or 1 guage multi-strand welding cables - I've checked
everything top to bottom and nothing has changed since the last time I ran
it with the old pig.
Questions ;
a) Why does the gap require so much current before firing? - When firing,
the sound is clean like when used with the old pig.
b) The transformer was totally refurbished before I got it so I am fairly
certain of the output - why does the current draw increase when voltage is
increased?
c) Why doesn't the increased voltage cause the gap to fire earlier
independent of current setting?
Coil performance is on par with the older transformer only now the voltage
is much higher and the current is higher also.
Thanks, and best regards
Robin Copini
p.s. based on the discussion on coil performance based on streamer
length/input power mine now has to be the most 'inefficient' coil on the
list :-)).